Olympus Camedia C-50 Zoom Review
The C-50 Zoom's automatic white balance coped in all our light conditions (no strong cast). The preset white balances for outdoor (Sunny / Overcast) and incandescent light were fairly good, the fluorescent preset less so. My biggest disappointment with the C-50 Zoom was a lack of manual white balance, a basic feature available on most manufacturers three megapixel 'entry level' digital cameras.
|Outdoors, Auto||Outdoors, Sunny||Outdoors, Overcast|
|Incandescent, Auto||Incandescent, Incandescent|
|Fluorescent, Auto||Fluorescent, Fluorescent|
I'm really a little stuck to understand how Olympus can call a 20/30 cm (w/t) minimum focus distance 'macro focus', it certainly allows you to get closer than the default 50 cm minimum focus distance but it's hardly macro capability. The best horizontal frame coverage was an unimpressive 10 cm with the lens set to full telephoto and the camera set approximately 30 cm from the subject. Poor.
The C-50 Zoom's built-in flash unit has a specified range of 3.4 m (11.2 ft) at wide angle and 2.0 m (6.6 ft) at telephoto (both at ISO 160). Our tests picked up a cool (blue) color cast on the skin tone test shot but a near perfect color balance on the test chart. Although we repeated the skin tone test a few times we got the same results. The C-50 Zoom does provide flash power compensation of +/- 2.0 EV in 0.3 EV steps.
|Skin tone - Good exposure, blue color cast on wall otherwise good skin color||Color patches - Good color balance, very slightly underexposed, +0.3 EV flash power compensation would have helped|
The C-50 Zoom has two methods for taking night exposures, it has a 'Night Scene' mode which locks aperture at its maximum and allows for shutter speeds as long as 4 seconds. Otherwise you can take manual exposures of up to 8 seconds. I preferred the later method, as you can see from the sample below the C-50 Zoom produces nice clean night exposures with no visible noise.
|Manual exposure: ISO 80, 8 sec, F4.0|
Barrel and Pincushion Distortion
The C-50 Zoom had slightly better than average distortion performance considering the size of the lens. We measured 1.1% barrel distortion at wide angle and no measurable pincushion distortion at telephoto.
|Barrel Distortion, 1.1% at wide angle||Pincushion Distortion, none at telephoto|
Vignetting / Light fall off
Our vignetting / light fall off test is very simple, a shot of a blank wall from two meters away, vignetting will always be most visible at wide angle and maximum aperture and will start to disappear at smaller apertures and/or further zoom. The C-50 Zoom exhibits very little corner vignetting / light fall off, there is just the hint of it most visible in the bottom corners, it's unlikely you would see this in a normal shot.
|Very moderate vignetting in the bottom corners of the frame at wide angle||No vignetting at telephoto|
Purple Fringing (Chromatic Aberrations)
The C-50 Zoom did exhibit some slight chromatic aberration around the edges of detail in high contrast areas of images taken at wide angle and/or maximum aperture. Having said that we only saw evidence of it in one or two our hundred or so 'every day' shots.
|Some fringing visible in the corners of shots with high contrast||Our standard chromatic aberration test shot|
Overall Image Quality / Specific Issues
The C-50 Zoom exhibited good resolution and sharpness (a little too aggressive at times). Color balance was also very impressive, an area Olympus appear to have improved considerably, color was natural and yet still 'punchy'. It is a shame that Olympus chose not to provide a manual white balance option.
Jagged diagonals / Demosaic artifacts
Something we noted in our C-5050 Zoom review was an artifact of either the cameras Demosaic or sharpening algorithms, it appears as jagged diagonals. Also related are visible Demosaic artifacts which appear as a dotted pattern around or along a line of detail.